"It should prompt serious work by health authorities to lower the risks further."
At least one economist says claims that there's a big influx of long-term returnees is a myth.
Data from property consultant CoreLogic was released on Thursday.
Dr Caroline McElnay announced the latest case update on Thursday.
Watch Thursday's media briefing here.
"If the evidence requires it, we will not hesitate."
India has reported nearly 80,500 new coronavirus cases in the past 24 hours.
Hydroxychloroquine is ineffective in preventing infection among people exposed to the new coronavirus.
Here are the latest developments from around the world overnight.